Refrigerating apparatus



Sept. l5, 1936. f c. R. WAYMANv REFRIGERATING APPARATUS .Filed Nov. 23,1931 2 Sheets-Sheet 1 ATTORNEYS Patented Sept. 15, 1936 PATENT oFFlcl?.g

yREFRIGERATIN G APPARATUS Charles R. Wayman, Dayton, Ohio, assignor, by

mesne assignments, to General Motors Corporation, a corporation ofDelaware v Application November 23, 1931, Serial No. 576,632 9 Claims.(Cl. 62-4) This invention relates to refrigerating apparatus and moreparticularly to control mechanisms therefor.

The objects of `my invention include the providing for a refrigeratingsystem-of an improved automatically operated switch mechanism having animproved selective manual control meansto.

be operated by the housewife for varying the operation o'f therefrigerating system; the provision of -an improved and attractivecoldcontrol means for a domestic refrigerator; the provision of a simpliedsingle wire or cable control for` the manual control means; land theprovision of a barrel type dial, improved modifying means on the switchmechanism, and improved connecting means for connecting the dial and themodifying means for indicating the effective position of the switchmodifying means..

Further objects and advantages of the present invention will be apparentfrom the following description, reference being had to the accompanyingdrawings, wherein a preferred form of the present invention is clearlyshown.

In the drawings:

Fig. l is a front view of a refrigerator embodying the inventionwith themachinery compartment exposed;

Fig. 2 is a fragmentary 'vertical sectional view of a refrigeratorcabinet showing the cold control dial; l

Fig. 3 is a fragmentary horizontal sectional view on the lines 3-3 ofFig. 2;

Fig. 4 is an enlarged front view of the cold control dial shown in Fig.l;

Fig. 5 is an elevational view of the switch mechanism, the cover ofwhich is shown in Fig. 1;

Fig. 6 is a fragmentary view of the `switch mechanism showing thecontrol or modifying means in quick freezing position;

Fig. '7 is a fragmentary view of Ithe switch mechanism showing thecontrol or modifying means in defrosting position, and

Fig. 8 is a section along the line 8-8 of Fig. 5.

Referring to theV drawings, and more particur larly to Fig. 1, there isshown for the purpose of illustrating my invention a refrigeratorcabinet having a food storage compartment 2| located in the upperportion of the cabinet and a machinery compartment 2E located in thelower portion'of the refrigerator' cabinet. Within the machinerycompartment 22 there is provided a com-r pressor 23 for compressing therefrigerant and for forwarding the refrigerant to a-condenser 24 wherethe refrigerant is condensed and liquefied and collected in the receiver25. From the reselective position.

' cage 46 mounted thereon-at one end 'and proceiver 25 the liquidrefrigerant is forwarded through the conduit 26 to an evaporator 21where the liquid refrigerant evaporates under reduced' pressure to coolthe food storage compartment 2l. The evaporated refrigerant is returnedfrom the evaporator to the compressor through the return conduit 2s.

An electric motor 29 is provided for driving the compressor through thepulley and belt means 30. This electric motor 29 is controlled to causethe lo operation of -the compressor according to the. pressure, andconsequently the temperature, of the evaporator 21 by means of a switchmeans 3l (shown in -Fig. 1 as enclosed within a cover) operated by meansof the pressure in the return l conduit 28 to which it is connected bymeans of an armored lconduit is used. 'Ihis manual control means is moreparticularly shown in Figs. 2- and 3. `For the purpose of receiving thisdial there is provided a notch or cavity 34 in the lower portion of thedoor jamb 35. Within this notch there is provided a U-shaped bracket 36which-receives a pivot pin 31 upon which the dial 32 is mounted. Thedial 32 is made of some suitable-material such as hard rubber orbakelite and is provided with an integral drum 38 at the side of thedial portion. The dial 32 is provided witha knurled rim having suitableindices 39 thereon for indicating the various selective positions of themanual control means.v A latch means 40 comprising a latch pin 4 I, alatch spring 42, and a spring housing 43 is provided in the rear portionof the U-shape-d bracket 36 and these members are so assembled that the-latch spring 42 resiliently urges the pin 4| into yengagement with thenotches upon the rear portion of the dial 32 to hold vthe dial in anydesired The drum 38 upon the dial 32 is connected by suitable cablemeans such 'as a. single wire 44 to a portion of thel manual controlmeans which is mounted upon 'the switch structure proper. The wire 44 isfastened to the drum by a screw 95.

Referring now to Figs. 5 to '8 inclusive, there is shown a switchplatform 45 having a bellows 55 For this reason, a single wire encased.1 25 v vided with afpair of upstanding ears 41 which pivotally support;an operating lever 48 at one end by means of a suitable pin 49. 'I'heoperating lever 48 is caused to move in successive vibrations by meansof the bellows 50 which is connected by means of -a suitable conduit tothe return conduit' 28 of the refrigerating system. At the other endofthe operating lever 48 there is provided a snap operating switchmechanism including a cam lever pivoted at an` intermediate point to theoperating lever 48 by means 'of the pin 92 and having a cam 52 at oneend which is acted upon by a cam roller 53ir/1ounted upon a lever 54.The lever 54 is pivoted at its lower end and provided with a suitablespring 55 which presses the cam roller 53 against the cam 52.

` 'I'he other end of the cam lever 5| is connected by means of aninsulating link 56 to' a pivoted upper contact 51 of a set of switchcontacts.-

This upper contact is pivoted at 58.

At the central portion of the operating lever 48 there is connected aspring adjusting means comprising a threaded pin 60 and a pair ofsprings 6| and 62, one above and one below the platform 45. Thesesprings may be adjusted uby suitable nuts and lock nuts 63 and 64positioned at the upper end of the spring 6| and at the lower end of thespring 62. As the pressure within the evaporator increases, the bellowswill expand to raiser the operating lever 48 against the pressure of thespring 62, thereby raising the cam lever 5| and this will cause the camroller 53 to ride from the upper face of the cam 52 to the lower face ofthe cam to trip the cam lever 5| in a counter-clockwise direction andthus to close the set of switch contacts 51 and 59. As-

the pressure in the evaporator has decreased because of the operation ofthe compressor 23, the bellows 50 will contract against the pressure ofthe spring 6| lowering the operating lever 48 and the cam lever 5|, thuscausing the cam roller 53 to ride from the lower face of the cam 52 tothe upper face thereof. In this way the cam lever 5| will be caused totrip in a clockwise direction and separate the switch contacts 51 and 59to stop the refrigerating apparatus.

In addition to the opposed spring adjustment connected to the centralportion of the operating lever 48, there is provided an additionaladjustment means designated in general by the reference character whichoperates upon the operating lever 48 only at the upper portion of itsvibrating movement. This adjusting means 18 comprises a plunger 1|having at its lowerl end a head 12 whichengages a free end of theoperating lever 48. The downward movement of the plunger 1| is limitedand therefore Adoes not a'ect the opening pressure of the switchmechanism but only the closing pressure. The plunger 1| is resilientlylurged in a downward direction by means of a spring `(not shown)enclosed Within an adjusting nut 13. This spring is adjusted by theadjusting nut 13. The adjusting means 10 is supported by means of aU-shaped bracket 14 which is mounted upon the platform 45.

A portion of the manual control means, specially constructed for usewith a single wire control, is mounted upon this bracket 14. Thisportion comprises a pivoted member which is pivoted upon a screw 16which is threaded into an up- `standing ear 11 Lwhich extends upwardlyfrom the upper portion of the bracket 14. Inasmuch as a single flexiblewire connecting means is used, yielding means are provided for returningthe pivoted member to retracted posiiton and for movement of theoperating lever 48 and thus the opening of the set of switch contacts 51and 59 is opposed by an increased resistance. The resistance means takesthe form of Aa pivoted lever .84 which is mounted upon a thick, headed,pin 85 riveted to the pivoted member 15. This ,pivoted lever 84 isresiliently urged in a clockwise direction by means of a suitable spring86 which is coiled about the pin 85 and has ends extending therefrom,one engaging a pin 81 upon the pivoted lever 84 and the other engaging atongue 88 which extends from the pivoted member 15.

A suitable stop 89 is provided for the pivoted lever 84 by turningoutwardly a'portion of the pivoted member 15. The wire 44 has beendescribed as having an end connected to the drum 38 upon the dial 32.'This wire 44 is threaded through an armored conduit 90 which is fastenedto the top of the platform 45 and then threaded through an aperture inthe tongue 88. The wire r44 has a stop 9| at the oppositeside of thetongue 88 for providing a limited movement in a clockwise direction ofthe pivoted member 15.

By rotating the dial 32 in a clockwise direction as viewed in Fig. 2,one end of the wire 44 will be wrapped upon the drum 38 to slowly pullthe other end through conduit 98 to pull the pivoted member 15 fromretracted position to one of the selective operating positions. Forexample, when the dial is moved from the position indicated as to thatindicated as 2, the outer end of the pivoted lever 84, which forms aresilient abutment, will engage the pin 92 which extends from theoperating lever 48. This will provide an increased resistanceopposingthe downward movement of the operating lever 48, and will opposethe opening of the switch contacts. eration of the compressor will beprolonged. By rotating the dial further, for example, .to the positionindicated upon the dial as 3 or 4 (not shown), the pivotedy member 15 isfurther rotated in a clockwise direction, moving the pivotv 85 of thelever 84 closer to the pin 92, thereby providing an increased resistanceby reason of' the shortened effective moment arm. Upon further rotationof the dial 32 to'the defrosting posi- In this way the option, notshown, the pivoted member 15 is pulled clockwise such a distance thatits front end, which` lhas a turned-in nose 93, strikes the cam lever 5|and separates the set of switch contacts 51 and 59 as shown in Fig. 7.This separating vofr the switch contacts prevents the operation of therefrigerating system until the dial is reset. By stopping-therefrigerating system for a suicient length of time the cooling unit 21will become warmer and the frost will melt therefrom.

My improved cold control is in the major part concealed. Only a portionof the manually operable dial is visible. 'It is simple, neat, andattractive. By providing a single wire control, the control issimplified.

While the forms of embodiment of the invention as herein disclosedconstitute a preferred form, it is to be understood that other formsbeing connected to means for varying the loading of the pressureresponsive means.

2. An automatic device for controlling a refrigerating system includingan electric switch structure for initiating and terminating operation ofthe system, pressure responsive meansfor operating said switchstructure, and means for varying the operation of said .switchstructure, said last.

mentioned means including' a barrel type manually operable dial having aplurality of selective operating positions, said dial being positionedremote from said switch structure, latch means for latching said dial inany one of said. selective positions, means mounted upon said switchstructure for controlling the operation thereof, and means operativelyconnecting said last mentioned means and said dial.

3. An automatic device for controlling a refrigerating system includingan electric switch structure for initiating and terminating operation ofthe system, means for operating said switch structure responsive tocertain conditions v of said refrigerating system. and means for varyingthe operation of said v switch structure, said last mentioned meansincluding a pivoted member mounted upon said switch structure, aresilient abutment mounted upon said pivoted member, said pivoted memberhaving means thereon for controlling said switch structure in oneposition to prevent operation of the system, means for urging saidpivoted member into retracted position, manually operable means mountedremotely from said switch structure for controlling the position of saidpivoted member,

said manually operable member having a plurality of selective positions,latch means for retaining said manually operable member in any one ofsaid selective positions, means for operatively 'connecting saidmanually operable member and s aid pivoted member, said manuallyoperable means when in one position being adapted to move said pivotedmember'from retracted position to cause said resilient abutment toengage said switch structure, and when in another vposition to causesaid means on said pivoted member to prevent operation of the system.

4. lAn automatic switch for controlling a refrigerating system includingan electric circuit, a switch structure including an operating memberhaving means connected thereto for opening and 'closing the circuit,means for imparting movement to said operating member, a movable membermounted upon said switch structure,

' said movable member having a 'resilient abutment means thereon adaptedto engage said operating member when said movable member is in oneselective position for varying the movement of the operating member,yielding means for returning said movable member to retracted position,and a single iiexible tension member con-1 `trol for said movable memberfor moving said 'lever in engagement with the projection and for varyingthe distance of the projection from the pivot of the pivoted lever tovary the' effective moment arm and thereby vary the resistance of theresilient modifying means.

6. A refrigeration l control structure having pressure responsive meansfor controlling the flow of a medium, said switch structure having avresilient modifying means including a projection and a pivoted leverresiliently urged against the projection, and means for varying thedistance off' the projection from the pivot of the pivoted lever to varythe effective moment arm and thereby to vary the resistance of theresilient modifying means.

,'7. Refrigeration control mechanism including a member to be actuated,an operating member therefor, means for imparting a plurality ofsuccessive vibrations to said operating member, said operating memberhaving a projection thereon; a pivoted lever resiliently urged in onedirection about its pivot, said lever being pivoted to a movablecarriage, and means for moving the movable carriage to cause theprojection to engage the pivoted lever.

8. Refrigeration control mechanism including a member to be actuated, anoperating member therefor, means for imparting a plurality of successivevibrations to said operating member, said operating member having aprojection thereon, a pivoted lever resiliently urged in one directionabout its pivot, said lever being pivoted to a movable carriage, andmeans for moving the movable carriage to cause the projection to engagethe pivoted lever and to vary the distance of the projection from thepivot oi the lever to vary the effective moment arm and Athereby varythe resistance tothe movement of the projection upon nism, and means toreturn the` control mechanism to normal and retain the tension typeconnecting means taut, n

CHARLES R. WAYMAN.

